Transposition of the Great Arteries (TGA)
Transposition of the great arteries (TGA) is the most common cyanotic (low blood oxygen) congenital heart defect.
Normally, the pulmonary artery comes off the right ventricle to pump deoxygenated (less oxygen content) blood to the lungs to get oxygen, while the aorta comes off the left ventricle to pump oxygenated blood from the lungs to the rest of the body.
In TGA, the arteries are switched. The aorta comes off the right ventricle and pumps deoxygenated blood to the body while the pulmonary artery comes off the left ventricle and pumps deoxygenated and oxygenated blood to the lungs.
To survive without intervention, there must be an additional defect that will allow the right and left side of the heart to communicate so that blood can mix. This defect can either be an atrial septal defect, ventricular septal defect, or a patent ductus arteriosus.
This condition occurs predominantly in males, with a 90 percent mortality rate within the first year of life if left untreated. Like most congenital heart defects, the cause is unknown.
Symptoms of Transposition of the Great Arteries
Symptoms such as cyanosis, a bluish color to the skin, usually appear at birth or shortly after birth. The severity of the symptoms depends on the size and type of the defects and how much oxygen moves through the body.
Other common symptoms include:
- TGA with no defect
- Severe cyanosis within 24 hours of life
- TGA with large ventricular septal defect (VSD)
- Mild cyanosis when crying, increased breathing rate, increased heart rate, sweating, and failure to gain weight over the first six weeks of life
- TGA with VSD and obstruction in left ventricle
- Extreme cyanosis at birth
- TGA with VSD and pulmonary artery obstruction
- Progressive cyanosis from birth
Diagnosis of Transposition of the Great Arteries
Your UT Southwestern Medical Center doctor may perform several tests to diagnose transposition of the great arteries. Common diagnostic tests include:
- Cardiac catheterization
- Usually done for infants whose echocardiogram does not provide enough information on the heart’s anatomy
- A noninvasive test that shows TGA and may also show other defects in the heart
- Hyperoxia test
- Shows oxygen saturation in blood
- Physical exam
- To determine whether baby’s mouth and skin are blue or if heart murmur can be heard with a stethoscope
Transposition of the Great Arteries Treatment Options
- Arterial switch surgery
- Dividing pulmonary artery and aorta from wrong ventricles and attaching them to the correct ventricles; also transferring coronary arteries to allow the heart to receive proper blood flow
- Balloon septostomy
- Increasing hole size between the right and left atria to allow for more mixing of the blood
- IV Prostaglandin E1
- Making the patent ductus arteriosus stay open and allow more mixing of the blood
Request an Appointment
To schedule an appointment with a transposition of the great arteries expert at UT Southwestern's facilities in Dallas or for more information about our services, request an appointment or call 214-645-8300.